Document feeder assisting device and image forming apparatus incorporating automatic document feeder including the document feeder assisting device

Abstract

A document feeder assisting device includes a document stacker to stack a document to be conveyed toward a feed port of an automatic document feeder, a pressing device to press the document toward a document placement surface of the document stacker, and a conveyance device to convey the document. The document is stacked on the document placement surface exposed above with the pressing device moved.

What is claimed is: 
     
       1. A document feeder assisting device attachable to an automatic document feeder of an image forming device, comprising:
 a document stacker to stack documents, creating a stack of documents, to be conveyed toward a feed port of the automatic document feeder; 
 a pressing device to press the stack of documents toward a document placement surface of the document stacker; 
 a conveyance device to convey a document, of the stack of documents, along a linear conveyance path, inclined relative to a conveyance path of the automatic document feeder, through an ejection port to a feed port of the automatic document feeder; and 
 an opening and closing device including an opening and closing member to open and close an ejection port to eject the document, the opening and closing member being energizable by an elastic force of an elastic member toward the document placement surface. 
 
     
     
       2. The document feeder assisting device of  claim 1 ,
 wherein the conveyance device is configured to transfer a force in a document conveyance direction to at least a part of a trailing end of the document to be conveyed, in the document conveyance direction, to convey the document toward the automatic document feeder. 
 
     
     
       3. The document feeder assisting device according to  claim 1 ,
 wherein the conveyance device includes a document conveying body to extrude the document from the stack of documents and a document conveying lever, and movement of the document conveying body is interlocked with movement of the document conveying lever to apply a force to a trailing end of the document to be conveyed in a document conveyance direction. 
 
     
     
       4. The document feeder assisting device of  claim 3 ,
 wherein the document conveying lever protrudes toward an operator to operate the document feeder assisting device to convey the document to be conveyed in the document conveyance direction. 
 
     
     
       5. The document feeder assisting device of  claim 3 ,
 wherein the conveyance device includes an elastic member to automatically return the document conveying lever and the document conveying body to respective home positions. 
 
     
     
       6. The document feeder assisting device of  claim 5 ,
 wherein a position of a center of gravity of components of the conveyance device, configured to move in conveyance of the document to be conveyed, and a position of a line of action of an elastic force by the elastic member substantially coincide with each other in a document width direction, orthogonal to the document conveyance direction. 
 
     
     
       7. The document feeder assisting device of  claim 5 , further comprising:
 an elastic member to automatically return the document conveying lever and the document conveying body to respective home positions; and 
 an elastic body including an elastic region, to buffer an impact of the document to be conveyed, 
 wherein a value, obtained by subtracting a distance from a document trailing end position in the document conveyance direction, when the documents are stacked, to a position of a nip of conveyance rollers closest to a feed port on a conveyance passage in the automatic document feeder from a sum of a maximum stroke amount of the document conveying lever and a length of the document in the document conveyance direction, is a positive value, 
 wherein a component to apply force in the conveyance direction to the document is retractable in a direction opposite to the conveyance direction by an amount of the value, and 
 wherein the amount by which the component is retractable, is within the elastic region of the elastic body. 
 
     
     
       8. The document feeder assisting device of  claim 3 , further comprising:
 a guide, to restrict movement of the document conveying lever and the document conveying body in the document conveyance direction. 
 
     
     
       9. The document feeder assisting device of  claim 1 ,
 wherein a central position of the opening and closing member and a central position of the document substantially coincide in the document width direction, orthogonal to the document conveyance direction. 
 
     
     
       10. The document feeder assisting device of  claim 1 ,
 wherein a pressing surface of the pressing device, to press the documents, is in contact with an uppermost surface of the stack of documents stacked on the document stacker and is movable in a thickness direction of the stack of documents in response to a thickness of the stack of documents. 
 
     
     
       11. The document feeder assisting device of  claim 10 ,
 wherein a line of action of resultant force of a pressing force, when the pressing surface of the pressing device presses the stack of documents, and a position of a center of gravity of the stack of documents on the document stacker, substantially coincide. 
 
     
     
       12. The document feeder assisting device of  claim 1 ,
 wherein inner walls, surrounding a space in the document stacker where the documents are stacked, are structured such that a distance, between inner walls facing each other and being parallel to each other in at least one of a document width direction and a document conveyance direction, relatively increases toward an upper end of the inner walls in a thickness direction of the document. 
 
     
     
       13. An image forming apparatus comprising:
 an automatic document feeder, including the document feeder assisting device of  claim 1  to convey the document toward the feed port of the automatic document feeder, in a vicinity of an intermediate portion of a conveyance passage. 
 
     
     
       14. A document feeder assisting device attachable to an automatic document feeder of an image forming device, comprising:
 an ejection port to eject a target document to be delivered to a feed port in the automatic document feeder; 
 a conveyance device to convey the target document toward the feed port of the automatic document feeder, the conveyance device including a document end extruder to extrude and deliver the document to the feed port; 
 a document stacker to receive the target document and a plurality of documents; and 
 an opening and closing member to open and close the ejection port in response to delivery of the target document,
 the opening and closing member contacting the document stacker to close the ejection port, 
 
 the document end extruder being formed with a curved surface to extrude a trailing end of a document in a document conveyance direction and to deliver the document to the feed port. 
 
     
     
       15. The document feeder assisting device of  claim 14 ,
 wherein, in a state in which a part of the document is in contact with conveyance rollers provided in a vicinity of the feed port of the automatic document feeder contacting when the document is delivered, in a document width direction orthogonal to the document conveyance direction, a distance, from a contact position on the curved surface being in contact with the trailing end of the document to a central position in the curved surface, is relatively shorter than a distance from a contact position between the conveyance rollers and the document to a central position in the curved surface. 
 
     
     
       16. The document feeder assisting device of  claim 14 ,
 wherein the curved surface formed on the document end extruder is set to form an orthogonal angle, or an angle less than 90 degrees, with respect to an inclined surface inclined downward from the curved surface in the document conveyance direction, and a height position of at least a part of a ridgeline between the inclined surface and the curved surface with respect to a document conveyance surface to convey the document in the document feeder assisting device, is set so as to be relatively higher than a document placement surface. 
 
     
     
       17. The document feeder assisting device of  claim 14 ,
 wherein a height position of conveyance of the document, with respect to a document conveyance surface to convey the document in the document feeder assisting device, is positioned between a height position of a nip portion of a pair of conveyance rollers arranged in a vicinity of the feed port of the automatic document feeder and a height position of a base of the curved surface formed on the document end extruder. 
 
     
     
       18. A document feeder assisting device attachable to an automatic document feeder of an image forming device, comprising:
 a conveyance device to convey a stack of documents stacked on a document placement surface, toward a feed port in the automatic document feeder, the conveyance being configured to feed one document of the plurality of documents and to restrict remaining ones of the plurality of documents stacked on the document placement surface, the feed port being disposed in the vicinity of an intermediate portion of a conveyance passage in the automatic document feeder; and 
 an opening and closing member, energizable in a direction toward the document placement surface by an energizing member and displaceable in the energizing direction to open and close an ejection port, 
 the opening and closing member including a first surface to contact the document placement surface when the opening and closing member closes the ejection port and a second surface to receive force, displacing the opening and closing member in a direction opposite to the energizing direction, when the opening and closing member opens the ejection port during document conveyance toward a feed port in the automatic document feeder. 
 
     
     
       19. The document feeder assisting device of  claim 18 ,
 wherein the second surface of the opening and closing member is orthogonal to the energizing direction. 
 
     
     
       20. An image forming apparatus comprising an automatic document feeder including the document feeder assisting device of  claim 14 , to convey the document toward the feed port in vicinity of an intermediate portion of a conveyance passage. 
     
     
       21. An image forming apparatus comprising an automatic document feeder including the document feeder assisting device of  claim 18 , to convey the document toward the feed port in vicinity of an intermediate portion of a conveyance passage.